期刊文献+
任意字段
题名或关键词
题名
关键词
摘要
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到86,392篇文章
< 1 2 … 250 >
每页显示 20 50 100
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
显示方式：
Quality-guaranteed Dubins Path Planning for USV Based on Mixed-integer Piecewise linear Programming for Addressing the Extended Minimum-time Intercept Problem 认领 引用 被引量：1
1
作者 Xing Zhou Kelin Zhu +3 位作者 Shuang Liu Zhaoqing Li Wenxin Zhang Kang Du 《哈尔滨工程大学学报（英文版）》 CSCD 2026年第1期216-227,共12页
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive... During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h2/(4√2),where h is the piecewise length. 展开更多
关键词 Minimum-time intercept problem Dubins vehicle Mixed-integer piecewise-linear program Linearization Approximate error trigonometric function USV
暂未订购 下载PDF
Reprogramming induced neurons from olfactory ensheathing glial cells: A feasible approach for spinal cord injury repair 认领 引用
2
作者 Javier Sierra María Portela-Lomba +1 位作者 Diana Simón M.Teresa Moreno-Flores 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第1期296-297,共2页
Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disruptin... Every year, around the world, between 250,000 and 500,000 people suffer a spinal cord injury(SCI). SCI is a devastating medical condition that arises from trauma or disease-induced damage to the spinal cord, disrupting the neural connections that allow communication between the brain and the rest of the body, which results in varying degrees of motor and sensory impairment. Disconnection in the spinal tracts is an irreversible condition owing to the poor capacity for spontaneous axonal regeneration in the affected neurons. 展开更多
关键词 injury feasible programming
暂未订购 下载PDF
Multi-phase trajectory programming with divert capability for lunar lander powered descent 认领 引用
3
作者 ZHANG Xiaowen WANG Dayi +2 位作者 HUANG Xiangyu LI Ji WANG Tianshu 《中国空间科学技术（中英文）》 CSCD 北大核心 2026年第3期143-156,共14页
It is important for a lunar lander to possess a large divert capability during the final landing phase,as this can enhance the tolerance for flight deviations in the early phase or improve the obstacle avoidance perfo... It is important for a lunar lander to possess a large divert capability during the final landing phase,as this can enhance the tolerance for flight deviations in the early phase or improve the obstacle avoidance performance.Therefore,when designing the powered descent trajectory,sufficient final phase divert capability should be reserved at the minimum propellant cost.To this end,a multi-phase trajectory programming(MPTP)method for powered descent with approaching phase divert capability is proposed.First,the entire powered descent trajectory is divided into the main braking phase and the approaching phase.The main braking phase is responsible for dissipating the majority of the initial velocity.The approaching phase is responsible for safely and precisely flying toward the landing site.It is nominally a vertical descent trajectory and possesses equal divert capability in all horizontal directions.Then,a constant-thrust linear tangent guidance(LTG)accounting for the lunar curvature is designed for the main braking phase.For the approaching phase,a variable-thrust lossless convex programming(LCP)guidance considering the constraints of tilt angle and glide-slope angle is developed.Subsequently,to connect the two phases and further optimize the propellant consumption throughout the entire trajectory,a method for determining the phase switching condition is proposed.The originally difficult-to-solve two-parameter optimization problem is decomposed into two more easily solvable subproblems,which are solved iteratively via a bilevel optimization framework.Finally,the divert capability of the proposed method is verified through numerical simulation.The programmed trajectory is basically consistent with the results of the pseudospectral method,with the difference in propellant consumption being only 0.006%.This method is suitable for the rapid iterative design of nominal trajectories for lunar lander powered descent in engineering applications. 展开更多
关键词 lunar landing powered descent trajectory programming multi-phase divert capability
暂未订购 下载PDF
DP1180双相钢在高应变速率下的力学性能及断裂行为 认领 引用
4
作者 董伊康 薛仁杰 +4 位作者 刘乐天 王学慧 赵楠 路洪洲 王立辉 《机械工程材料》 CAS CSCD 北大核心 2026年第1期58-64,共7页
对DP1180双相钢进行准静态(应变速率0.001,0.01s-1)和动态(应变速率0.1,1,10,50,100,200,500,1000 s-1)拉伸试验,研究了其力学特征、断裂行为以及微观结构演变规律。结果表明:随着应变速率增加,DP1180双相钢的抗拉强度、屈服强度... 对DP1180双相钢进行准静态(应变速率0.001,0.01s-1)和动态(应变速率0.1,1,10,50,100,200,500,1000 s-1)拉伸试验,研究了其力学特征、断裂行为以及微观结构演变规律。结果表明:随着应变速率增加,DP1180双相钢的抗拉强度、屈服强度、断后伸长率和均匀伸长率均增大,高应变速率(100~1000 s-1)下屈服强度的应变速率敏感性相比抗拉强度更大。随着应变速率增加,拉伸试样表面微观形貌由断层状变为撕裂状,横向微裂纹数量增多,但当应变速率达到1000 s-1时横向裂纹几乎消失,出现大量微孔洞型断裂形态。不同应变速率下DP1180双相钢均发生微孔聚集型韧性断裂,随着应变速率增加,断口处大尺寸韧窝数量增多,韧窝中心出现由马氏体破碎形成的较深孔洞。高应变速率拉伸后钢中的马氏体板条较细,位错密度较大。位错强化和马氏体变形是高应变速率下强度增大的主要原因;绝热温升激活马氏体的塑性变形能力则是塑性增大的主要原因。 展开更多
关键词 DP1180双相钢 应变速率 力学性能 断裂行为
暂未订购 下载PDF
H∞Optimal Output Regulation of Unknown Linear Systems via an Adaptive Dynamic Programming and Internal Model 认领 引用
5
作者 Yong-Sheng Ma Jian Sun Yong Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第6期1314-1324,共11页
This paper delves into the H∞optimal output regulation problem for continuous-time linear systems with an unknown system model.By integrating the internal model principle with optimal control,we derive an optimal con... This paper delves into the H∞optimal output regulation problem for continuous-time linear systems with an unknown system model.By integrating the internal model principle with optimal control,we derive an optimal control policy and a worst-case disturbance policy through the formulation and solution of a zero-sum game problem.Subsequently,leveraging adaptive dynamic programming,we propose a policy iteration learning algorithm capable of learning both the optimal control policy and the worst-case disturbance policy directly from system data.The existing algorithms necessitate an initial stabilizing policy,a full-rank condition,and the storage of historical data to guarantee algorithm convergence.In contrast,we design a dual policy iteration algorithm equipped with an online learning mechanism,thereby eliminating these additional prerequisites.Simulation results with an antonomous ground vehicle underscore the effectiveness of our proposed algorithm,and its superiority is further demonstrated through comparisons with existing methodologies. 展开更多
关键词 Adaptive dynamic programming internal model principle optimal control output regulation
暂未订购 下载PDF
Open-loop control of combustion instabilities in a full-scale annular ramjet combustor using linear genetic programming 认领 引用
6
作者 Jianguo TAN Zheng XU +2 位作者 Yao LIU Dongdong ZHANG Yi HOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第2期20-28,共9页
The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programmi... The operational demands of a wide range significantly exacerbate combustion instability issues within ramjet combustor.To suppress combustion oscillations,an open-loop control system utilizing Linear Genetic Programming(LGP)has been developed for a full-scale annular ramjet combustor.The LGP is used to generate control laws that include multi-frequency forcing.These laws are then transformed into square waves to actuate the solenoid valve,which modulates the kerosene supply for open-loop control.The results show that the duty cycle has little effect on instability amplitude,whereas an increase in frequency leads to a remarked reduction in combustion amplitude.After five generations evolvements,the pressure amplitude is reduced by 40.6% under the optimal control law generated by LGP.Furthermore,the machine learning process is depicted using a proximity map of control law similarity,with the search pathway visualized by the steepest descent.All individuals go forward to the upper left corner of the map with the evolution process,terminating at the optimal individual of the fifth generation. 展开更多
关键词 Annular ramjet combustor Combustion instabilities Linear genetic programming Machine learning Open-loop control
暂未订购 下载PDF
Thermal performance optimization in CuO-water nanofluid enclosure with sinusoidal heating using deep learning and multi-expression programming 认领 引用
7
作者 Naeem Ullah Aneela Bibi +1 位作者 Yufeng Nie Dianchen Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第5期24-48,共25页
Natural convection in enclosures containing nanofluids has attracted significant attention due to its relevance in thermal management systems.In this context,this study presents a comprehensive numerical investigation... Natural convection in enclosures containing nanofluids has attracted significant attention due to its relevance in thermal management systems.In this context,this study presents a comprehensive numerical investigation of flow and heat transfer in a square cavity saturated with water-based CuO nanofluid having a centrally placed sinusoidal-shaped heated element.All the enclosure walls satisfy the no-slip velocity condition.Thermally,the vertical walls are kept at a cold reference temperature,the lower wall is partially heated at its center,and the remaining portions of the lower and entire upper walls are adiabatic.The internal sinusoidal element is also uniformly heated.The flow dynamics and thermal fields are governed by the two-dimensional steady-state Navier-Stokes and energy equations,solved using the Galerkin finite element method.Additionally,a novel hybrid approach integrating multi-expression programming(MEP)technique with a convolutional neural network bidirectional gated recurrent unit(CNN-BiGRU)deep learning network is also applied to enhance flow and thermal prediction accuracy.This hybrid approach enables precise evaluation of how heater waviness,magnetic field orientation,and nanoparticle dispersion influence flow structure and heat transfer.Results reveal stronger convection at high Rayleigh numbers,magnetic damping at increased Hartmann numbers,and higher temperatures with reduced velocity at greater nanoparticle concentrations.Among the analyzed situations,increasing heater waviness improves heat-transfer performance.Both the MEP and CNN-BiGRU models accurately capture the key features of flow and heat transport trends,indicating that the hybrid approach provides enhanced predictive capability for complex convection-driven nanofluid systems. 展开更多
关键词 Magnetohydrodynamic convection Nanofluid flow simulation Sinusoidal heated source Deep learning Multi-expression programming
暂未订购 下载PDF
Entry trajectory optimization for cross-domain morphing vehicles by hybrid sequential second-order cone programming 认领 引用
8
作者 Zheng Li Zhenyue Jia +2 位作者 Zheng Fang Hongmiao Zhou Jianqiao Yu 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第4期149-175,共27页
This paper proposes a hybrid sequential second-order cone programming(HSSOCP)method with a three-layer scheme for the entry trajectory optimization of the cross-domain morphing vehicles(CDMVs).By defining the new morp... This paper proposes a hybrid sequential second-order cone programming(HSSOCP)method with a three-layer scheme for the entry trajectory optimization of the cross-domain morphing vehicles(CDMVs).By defining the new morphing rate control variable and using relaxation techniques to relax the bank angle constraint,the SOCP-based entry problem is constructed.A dynamic relaxation penal-ization technique is developed in the first layer to overcome artificial infeasibility and significantly enhance initialization robustness.A novel standard oscillation identification(SOI)method is proposed to precisely identify the iteration oscillations of basic SSOCP in the second layer,which can significantly improve the solution accuracy.A soft-trust-region strategy is applied in the third layer to eliminate oscillations and accelerate convergence.Simulation results of two scenarios demonstrate that the proposed SOI method effectively avoids non-standard oscillation interference versus traditional methods.The morphing aircraft can complete tasks better with a 7.01%and 10.43%reduction in heat load respectively compared to fixed-wing aircraft.The HSSOCP method can maintain accuracy while reducing computation time by 63.47%and 73.86%versus VATSSOCP.Monte Carlo simulations further validate the robustness. 展开更多
关键词 Cross-domain vehicle Morphing vehicle Entry trajectory optimization Sequential second-order cone programming Iteration oscillation Hybrid scheme
暂未订购 下载PDF
DP590钢表面处理对复合层板的层间结合性能优化分析 认领 引用
9
作者 沈智 施进科 +3 位作者 安家菊 金康 郭平安 刘克明 《锻压技术》 CAS CSCD 北大核心 2026年第7期88-94,132,共7页
为研究DP590钢/玻璃纤维复合层板的层间结合性能,对DP590钢板进行了机械打磨、喷砂、电泳3种表面处理,通过表面组织观察和滚筒剥离试验相结合的方法,对表面处理工艺参数进行了对比研究。结果表明:表面组织的均匀性和有效接触面积是影响... 为研究DP590钢/玻璃纤维复合层板的层间结合性能,对DP590钢板进行了机械打磨、喷砂、电泳3种表面处理,通过表面组织观察和滚筒剥离试验相结合的方法,对表面处理工艺参数进行了对比研究。结果表明:表面组织的均匀性和有效接触面积是影响复合层板层间结合性能的两个主要因素,最终对比得出电泳处理20 min后的DP590钢板与玻璃纤维的结合性能最佳;在此参数下生产的复合层板的层间剥离强度达到214.2(N·mm)·mm-1;提出的表面处理工艺应用于汽车电池包上盖的生产中,满足验证要求,可以拓展纤维金属复合层板在汽车领域中的应用范围。 展开更多
关键词 DP590钢 玻璃纤维 复合层板 表面处理 表面组织 结合性能 剥离强度
暂未订购 下载PDF
DP980高强度双相钢板韧性断裂建模及冲裁工艺模拟 认领 引用
10
作者 韩国丰 丁子涵 +5 位作者 崔振祥 牛超 韩非 张凌宇 何霁 李淑慧 《锻压技术》 CAS CSCD 北大核心 2026年第6期154-164,共11页
为精准预测DP980高强度双相钢板在冲裁过程中的断裂行为,采用实验与有限元仿真相结合的方法,标定了其韧性断裂模型参数,并将该模型应用于冲裁工艺仿真。研究了一种基于应力不变量的断裂模型,通过设计并制备中心孔拉伸、缺口拉伸及面内... 为精准预测DP980高强度双相钢板在冲裁过程中的断裂行为,采用实验与有限元仿真相结合的方法,标定了其韧性断裂模型参数,并将该模型应用于冲裁工艺仿真。研究了一种基于应力不变量的断裂模型,通过设计并制备中心孔拉伸、缺口拉伸及面内剪切试样,结合数字图像相关(DIC)技术与有限元分析,标定了DP980钢在单向拉伸、平面应变及剪切等多种典型应力状态下的断裂应变及应力路径。材料的塑性行为采用Swift-Voce混合硬化模型进行描述,断裂模型参数则通过遗传算法进行优化。将最终标定的模型应用于DP980钢板的冲裁过程仿真,预测结果与实验结果吻合良好,验证了所构建断裂模型在模拟复杂冲裁工艺中的准确性。 展开更多
关键词 DP980高强钢 韧性断裂模型 冲裁工艺 数字图像相关技术 断裂应变
暂未订购 下载PDF
Entry trajectory optimization for cross-domain morphing vehicles using oscillation-avoidance-based multistage trust-region sequential convex programming 认领 引用
11
作者 Zheng LI Zheng FANG +1 位作者 Zhenyue JIA Jianqiao YU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2026年第4期310-333,共24页
This paper develops an Oscillation-avoidance-based Multistage Trust-region Sequential Convex Programming(OMTSCP)method for the highly nonlinear entry trajectory optimization problem of Cross-Domain Morphing Vehicles(C... This paper develops an Oscillation-avoidance-based Multistage Trust-region Sequential Convex Programming(OMTSCP)method for the highly nonlinear entry trajectory optimization problem of Cross-Domain Morphing Vehicles(CDMVs).The decoupling of states and controls for complex nonlinear dynamics is achieved by defining new control and state variables.A series of sub convex problems is formulated by successive linearization and discretization of the constraints.The proposed Trust-region Sequential Convex Programming(TSCP)scheme consists of three stages:an initial guess generation stage,a basic solution stage,and an optimal solution stage.An approach to penalize the dynamic relaxation is firstly developed to obtain an initial guess with considerable accuracy and significantly improve the robustness of the algorithm by overcoming the drawbacks of potential artificial infeasibility.The oscillation phenomenon of the TSCP method under rectangular trust region is then investigated,and a novel N-shape-based oscillation identification method is proposed to identify the oscillation accurately.Finally,an oscillation-avoidance method based on the sort trust-region is proposed to improve the convergence of the TSCP algorithm.Numerical comparisons of the proposed method and a typical TSCP method,as well as the morphing and fixed-morphing vehicles are provided to demonstrate the effectiveness and efficiency of the proposed method and the performance advantages of the morphing vehicle.The robustness of the method is further verified by Monte Carlo simulation. 展开更多
关键词 Convex optimization Cross-domain vehicle Entry trajectory optimization Morphing vehicle Multistage Oscillation phenomenon Trust-region sequential convex programming
暂未订购 下载PDF
预变形对DP590双相钢性能的影响 认领 引用
12
作者 张茜 牛星辉 +1 位作者 刘淑影 王嘉伟 《锻压技术》 CAS CSCD 北大核心 2026年第2期259-265,299,共7页
以DP590双相钢为研究对象,采用单轴拉伸试验对较大尺寸试样施加预变形量为0%、3%、6%、9%、12%和15%的6种预变形,卸载后采用线切割制样并准静态拉伸至失效,获取其力学性能、加工硬化行为和局部成形性能的演变规律。结果表明:随着预变形... 以DP590双相钢为研究对象,采用单轴拉伸试验对较大尺寸试样施加预变形量为0%、3%、6%、9%、12%和15%的6种预变形,卸载后采用线切割制样并准静态拉伸至失效,获取其力学性能、加工硬化行为和局部成形性能的演变规律。结果表明:随着预变形量的增加,DP590钢的强度升高,规定非比例延伸强度变化尤为明显,屈强比逐渐趋近于1,总伸长率轻微升高,且多道次成形更利于全局成形;预变形会改变材料的加工硬化行为,无预变形时DP590钢在小应变范围内加工硬化特性突出,而预变形后在大应变范围内加工硬化更显著,随着预变形量的增加,材料加工硬化能力降低;局部成形性能随着预变形量的增加呈线性降低趋势。针对拉延后翻边/整形零件,可将预变形量控制在6%~9%,以平衡后续型面特征成形和边缘局部抗裂需求。 展开更多
关键词 预变形 DP590双相钢 力学性能 加工硬化性能 局部成形性能
暂未订购 下载PDF
DP600双相钢不同应变速率下的力学性能和本构模型 认领 引用
13
作者 罗森侨 罗通强 张振伟 《锻压技术》 CAS CSCD 北大核心 2026年第7期248-255,共8页
针对DP600双相钢,探究了不同应变速率下材料的关键力学性能的演变规律;通过扫描电镜对比分析了不同应变速率下拉伸试样的断口微观形貌特征;选取Johnson-Cook模型、修正Johnson-Cook模型、Cowper-Symonds模型等对不同应变速率下材料的力... 针对DP600双相钢,探究了不同应变速率下材料的关键力学性能的演变规律;通过扫描电镜对比分析了不同应变速率下拉伸试样的断口微观形貌特征;选取Johnson-Cook模型、修正Johnson-Cook模型、Cowper-Symonds模型等对不同应变速率下材料的力学性能开展外延拟合,并与试验结果进行误差分析;基于帽形截面梁冲击试验与仿真对比分析,验证了3种模型的预测精度,获取了DP600双相钢的动态力学性能最优本构模型。结果可知:DP600双相钢表现出较强的应变速率正敏感性,且关键力学性能指标随应变速率的演化规律呈现出明显的差异性;随应变速率提升,试样的断口韧窝密度逐渐增大,尺寸则先减小后增加;采用修正Johnson-Cook模型表征动态力学性能的精度较高,拟合曲线关键参数的最大误差为2.53%,帽型截面梁冲击峰值载荷误差仅为0.8%、平均载荷误差为4.16%,可将此模型应用于整车碰撞仿真。 展开更多
关键词 DP600双相钢 本构模型 力学性能 断口形貌 落锤冲击
暂未订购 下载PDF
DP1200高强钢激光焊接数值模拟与工艺研究 认领 引用
14
作者 王艳杰 祖健豪 +2 位作者 杨海鑫 李源欣 李帅 《北华航天工业学院学报》 CAS 2026年第2期14-18,共5页
探讨激光焊接工艺参数对DP1200高强钢激光焊接接头性能的影响。通过有限元方法建立了三维数值模型,利用圆锥形热源模型对激光焊接过程进行模拟。采用光纤激光对1.2mm厚DP1200高强钢进行激光焊接,研究了从高到低不同热输入量(900J/cm~180... 探讨激光焊接工艺参数对DP1200高强钢激光焊接接头性能的影响。通过有限元方法建立了三维数值模型,利用圆锥形热源模型对激光焊接过程进行模拟。采用光纤激光对1.2mm厚DP1200高强钢进行激光焊接,研究了从高到低不同热输入量(900J/cm~180J/cm)对焊接接头低倍截面形貌、抗拉强度和硬度的影响。研究结果表明,热输入量对焊缝截面熔宽影响显著,熔宽随着焊接热输入量的降低而变窄,焊接接头未出现冷裂纹,有轻微咬边缺陷;随着热输入的减少,马氏体含量增多,焊缝硬度增加;焊接热影响区出现轻微的软化现象;模拟激光焊接接头与实际焊接结果吻合度达到90%,验证了模拟结果的准确性和可靠性;同时获得1.2mm厚DP1200高强钢激光焊接工艺窗口,即激光功率为1500W,热输入量为450J/cm~300J/cm时,焊接接头形貌和力学性能良好。 展开更多
关键词 激光焊接 DP1200钢 热输入量 数值模拟 力学性能
暂未订购 下载PDF
HC340/590DP+Z高强度双相钢硬化模型研究 认领 引用
15
作者 余建华 赵同铭 《锻压技术》 CAS CSCD 北大核心 2026年第5期307-314,共8页
高强度钢的硬化模型对成形仿真、碰撞性能预测及结构耐久性分析等具有重要影响,针对HC340/590DP+Z高强度双相钢的最优适用硬化模型开展分析。获取单向拉伸的真应力-真应变曲线,基于5种单一硬化模型和2种组合硬化模型开展参数拟合和精度... 高强度钢的硬化模型对成形仿真、碰撞性能预测及结构耐久性分析等具有重要影响,针对HC340/590DP+Z高强度双相钢的最优适用硬化模型开展分析。获取单向拉伸的真应力-真应变曲线,基于5种单一硬化模型和2种组合硬化模型开展参数拟合和精度分析;基于液压胀形试验获取大应变范围的有效应力-塑性应变曲线,验证各硬化模型在大应变范围的性能预测精度;选取3种高精度的硬化模型,对比杯突试验与有限元仿真的关键性能偏差,进一步验证模型的预测精度。结果表明:单向拉伸标定的模型决定系数较高,但各模型对大应变应力的预测趋势差异显著;大应变下,HC340/590DP+Z钢的强度呈递增趋势,液压胀形与单向拉伸曲线贴合度较高;Swift+Hockett-Sherby组合模型对大应变性能的预测精度最高,决定系数为0.9921,且杯突仿真与实测载荷-位移曲线高度一致,最大载荷和极限应变偏差分别为1.11%和0.29%,表明Swift+Hockett-Sherby组合模型可高精度地预测大应变HC340/590DP+Z钢的力学性能,并为相关工程分析提供参考。 展开更多
关键词 HC340/590DP+Z高强度双相钢 力学性能 硬化模型 液压胀形试验 杯突试验
暂未订购 下载PDF
亚麻E2F/DP转录因子基因家族鉴定及表达分析 认领 引用
16
作者 刘萍萍 孙阎 +11 位作者 刘丹丹 唐立郦 杨洌 程莉莉 康庆华 宋喜霞 姜忠娟 刘烨 孙茹 吴广文 杨学 袁红梅 《江苏农业学报》 CSCD 北大核心 2026年第2期250-263,共14页
为明确亚麻E2F/DP家族基因的生物信息学特征及其在作物生长发育过程中的影响机制,本研究通过生物信息学方法,分析亚麻E2F/DP家族基因结构、顺式作用元件、染色体定位、物种内和物种间共线性特征,及其编码蛋白质的理化性质和互作网络,并... 为明确亚麻E2F/DP家族基因的生物信息学特征及其在作物生长发育过程中的影响机制,本研究通过生物信息学方法,分析亚麻E2F/DP家族基因结构、顺式作用元件、染色体定位、物种内和物种间共线性特征,及其编码蛋白质的理化性质和互作网络,并利用转录组测序(RNA-seq)技术分析不同激素处理下亚麻E2F/DP基因的表达模式。结果表明,亚麻基因组中共鉴定到14个E2F/DP家族基因,其中有7个属于E2F亚家族,3个属于DP亚家族,4个属于DEL亚家族;同一亚家族的E2F/DP基因结构及其编码蛋白质的保守基序分布、保守结构域高度相似。物种内共发现16对共线性基因,且存在共线性的两个基因位于不同的染色体上。亚麻E2F/DP家族基因启动子序列中含有丰富的光响应元件、激素响应元件、胁迫响应元件、发育过程特定元件等。3个DP亚家族蛋白质(Lus10014423、Lus10022620和Lus10023926)为关键枢纽蛋白。不同激素处理后,亚麻茎部中段、茎部下段与叶片中14个E2F/DP家族基因均呈现差异性表达,基于实时荧光定量PCR(qRT-PCR)得到的Lus10022620和Lus10039455基因相对表达量与转录组测序结果在变化趋势上基本一致。本研究结果为进一步开展激素对亚麻E2F/DP转录因子的调控机制研究提供了基础。 展开更多
关键词 亚麻 E2F/DP家族基因 转录因子
暂未订购 下载PDF
华南飑线中闪电活动与ZDR和KDP柱的时空配置关系研究 认领 引用
17
作者 翟慧妍 赵川鸿 +6 位作者 张义军 郑栋 徐良韬 姚雯 肖辉 杜赛 陈家福 《气象学报》 CAS CSCD 北大核心 2026年第3期593-608,共16页
基于广州S波段双偏振雷达和低频三维闪电探测系统,研究了2017年5月4和8日两次飑线过程中闪电活动与ZDR和KDP柱的时空配置关系。结果表明:(1)闪电活动初期(云闪频次低于50次/(6 min)、地闪频次低于10次/(6 min)),云闪和地闪活动主... 基于广州S波段双偏振雷达和低频三维闪电探测系统,研究了2017年5月4和8日两次飑线过程中闪电活动与ZDR和KDP柱的时空配置关系。结果表明:(1)闪电活动初期(云闪频次低于50次/(6 min)、地闪频次低于10次/(6 min)),云闪和地闪活动主要落在ZDR和KDP柱平面空间覆盖范围内,云闪更倾向于发生在KDP柱区域内(占比最大可超过40%)。随着闪电活动的活跃,云闪和地闪活动主要落在非ZDR和KDP柱平面覆盖范围。(2)ZDR和KDP柱体积变化可提前云闪和地闪活动趋势约30 min,相关系数可超过或接近0.9,且ZDR柱体积峰值可以较好地预示云闪和地闪峰值的出现。 展开更多
关键词 飑线 闪电活动 ZDR和KDP柱 时空配置
暂未订购 下载PDF
基于ADP的非对称约束系统动态事件触发方法 认领 引用
18
作者 薛珊 赵宁 张卫东 《自动化学报》 EI CAS CSCD 北大核心 2026年第6期1209-1220,共12页
本文提出一种基于自适应动态规划的动态事件触发方法(DEM),用于解决具有状态与控制双重非对称约束的非线性连续时间系统最优控制问题.首先,利用非线性映射函数将非对称约束系统的控制问题转化为无约束形式.然后,设计一种静态事件触发方... 本文提出一种基于自适应动态规划的动态事件触发方法(DEM),用于解决具有状态与控制双重非对称约束的非线性连续时间系统最优控制问题.首先,利用非线性映射函数将非对称约束系统的控制问题转化为无约束形式.然后,设计一种静态事件触发方法(SEM),其中触发条件仅与当前状态相关.进一步,开发一种依赖额外内部动态变量的DEM,其触发条件也与系统历史信息相关.事实上,DEM是SEM的进阶方法.理论分析证实DEM在确保系统性能的情况下,能够进一步节省计算和网络资源.最后,介绍基于神经网络的实现方法.在无人水面艇仿真实验环境下,该方法的有效性得到了验证. 展开更多
关键词 自适应动态规划 自适应评价设计 神经网络 事件触发方法 动态事件触发方法
暂未订购 下载PDF
梯级水电站联合发电调度补偿效益分摊的GNDP法 认领 引用
19
作者 郭毅 郭俊 +3 位作者 兰芳 路佳豪 纪宸 何中政 《水电能源科学》 北大核心 2026年第5期221-225,共5页
梯级水电站联合发电调度补偿效益科学合理分摊是我国各大流域梯级水电站多业主达成合作的重要前提。在补偿效益分摊时,还需注意各个体参与联盟的稳定性。在考虑联盟稳定性分摊方法中,提出了成员参与和退出联盟前后的联盟与成员收益损失... 梯级水电站联合发电调度补偿效益科学合理分摊是我国各大流域梯级水电站多业主达成合作的重要前提。在补偿效益分摊时,还需注意各个体参与联盟的稳定性。在考虑联盟稳定性分摊方法中,提出了成员参与和退出联盟前后的联盟与成员收益损失比指标,依据各成员指标值相等时确定分摊方案。为此,针对DP和MDP法指标值缺乏明确参考值的问题,引入几何平均数,提出了补偿效益分摊的几何归一化DP法(GNDP),并将其应用于赣江中游梯级水电站联合发电调度补偿效益分摊中。结果表明,单指标法和变异系数法结果无法满足补偿效益分摊前提条件中的子集效益保障条件;MDP和DP法根据M(i)和D(i)指标进行分摊,缺乏有效的参考依据,而GNDP法通过调整分摊比例确保G(i)接近1.00即可,操作简便且判定条件清晰,研究结果可为补偿效益分配提供参考。 展开更多
关键词 补偿效益分摊 梯级水电站 DP法 几何平均数 发电调度
暂未订购 下载PDF
西瓜ClE2F/DP家族全基因组鉴定及其在瓜蚜胁迫下的表达模式分析 认领 引用
20
作者 陈黎明 杨启帆 +3 位作者 张千一 张爱环 张志勇 郭洪刚 《应用昆虫学报》 CAS CSCD 北大核心 2026年第2期328-338,共11页
【目的】探究西瓜Citrullus lanatus ClE2F/DP基因家族对瓜蚜Aphis gossypii的抗蚜作用。【方法】使用MEGA7、TBtools、MEME等对西瓜ClE2F/DP家族进行全基因组鉴定和生物信息学分析,并利用qRT-PCR分析了瓜蚜取食前后西瓜ClE2F/DP基因的... 【目的】探究西瓜Citrullus lanatus ClE2F/DP基因家族对瓜蚜Aphis gossypii的抗蚜作用。【方法】使用MEGA7、TBtools、MEME等对西瓜ClE2F/DP家族进行全基因组鉴定和生物信息学分析,并利用qRT-PCR分析了瓜蚜取食前后西瓜ClE2F/DP基因的相对表达量。【结果】共鉴定西瓜基因组中有6个ClE2F/DP成员,其中ClE2FA、ClE2FC为第一类不稳定亲水酸性蛋白,ClDP为第二类二聚蛋白,ClE2FE1为第三类不稳定亲水碱性蛋白,而且结合结构以及已有文献报道推测二聚蛋白ClDP及不稳定亲水碱性蛋白ClE2FEC、ClE2FE1可能参与植物抗病虫害过程。ClE2FA在蚜虫取食24 h后基因表达量上调2.5倍,ClE2FE1在蚜虫取食48 h后基因表达量先上调2.1倍,随后在取食72 h后表达量下调1.7倍;ClE2FC、ClDP在蚜虫取食24 h后显著下调超过2倍(P<0.001),说明西瓜ClE2F/DP基因响应瓜蚜取食。【结论】西瓜ClE2F/DP基因家族在响应蚜虫取食时存在显著的异质性。 展开更多
关键词 西瓜 E2F/DP转录因子 生物信息学 瓜蚜侵染 基因表达模式
暂未订购 下载PDF
已选0条
引用分析
参考文献
引证文献
 统计分析
检索结果
已选文献
上一页 1 2 … 250 下一页 到第 页
在线咨询 使用帮助 返回顶部 意见反馈